1. Field of the Invention
The present invention relates to an apparatus having a self-repairing function which implements a self-repair of a fault which prevents the apparatus from satisfactorily performing a given function, and a method of self-repairing the apparatus.
2. Related Art
It has been proposed in the field of image forming apparatus such as copying machines to additionally provide a so-called self-repairing function. The self-repairing function is intended to make diagnoses and repairs on functions relative to image forming for maintenance. Typical apparatus having such self-repairing function is disclosed in Japanese Unexamined Patent Publication No. 2-252121 (1990).
In the apparatus disclosed in this publication, a function to be maintained is monitored by checking whether the function is active or not, and the repair of the function is achieved by actuating another function which can substitute for the function to be maintained.
That is, the conventional self-repairing function employs so-called "two-choices" diagnosing and repairing approaches and, therefore, does not take into consideration degrees of functional degradation and functional recovery. This may be attributed to the difficulty in quantifying the abstract concept of functions.
Accordingly, the conventional self-repairing function makes an extreme choice in a certain sense, which includes such choices that other functions are abandoned for the maintenance of a particular function A, and that a method of repairing (a) for a particular function A is not employed because the method may influence the other functions.